package netjava;
// 泛型的定义
// 使用
public class Cat<T extends Number> {
    T sex;
    private int age;

    static{
//        T t1;
    }
    public T getSex() {
        return sex;
    }

    public Cat<T> setSex(T sex) {
        this.sex = sex;
        return this;
    }


    public  void fn3(){
//        new T();
        //T[] arr = new T[5];
    }
    public static <E> void fn2(E e){

    }

    public static void main(String[] args) {
        Cat<Integer> cat1 = null;
        Cat<Double> cat2 = null;
       /* fn1(cat1);
        fn1(cat2);*/

      /* Cat<Object> cat = null;
       fn1(cat);*/


    }

    //下限  上限
    public static void fn1(Cat<? super Number> cat){

    }
}
